Bump stop device

ABSTRACT

The invention concerns a vehicle bump stop comprising a rolling bearing forming a stop element ( 8 ), a support spring retainer ( 11 ), and an elastic support block ( 2 ), the rolling bearing including an upper race ( 12 ) arranged in an annular upper cap ( 16 ) forming a contact surface between said upper race ( 12 ) and the elastic block ( 2 ), a lower race ( 13 ). The device comprises an annular lower cap ( 17 ) forming a contact surface between the lower race ( 13 ) and the support spring retainer ( 11 ). The caps ( 16, 17 ) comprise each a thick portion ( 18, 22 ) and a thin portion ( 19, 23 ), the thin portion ( 19, 23 ) being located axially opposite the thick portion ( 22, 18 ) of the other cap, the lower ( 13 ) and upper ( 12 ) races being urged to be pressed on the thick portions ( 22, 18 ) of the lower ( 17 ) and upper ( 16 ) caps forming a rolling bearing with oblique contact.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of suspension bump stopsused, in particular, in motor vehicles on the telescopic suspensionstruts of the steered wheels.

2. Description of the Relevant Art

A suspension bump stop usually includes an upper race and a lower racebetween which are placed rolling elements, in the form of balls orrollers.

A suspension bump stop is usually placed at the top of the suspensionstrut between a lower metal cup that also acts as a seat for asuspension spring, and an upper element secured to the vehicle body. Thespring of the suspension device is installed around the rod of thedamper piston whose end is secured to an elastic support block. Thesuspension bump stop bearing allows a rotating motion between the springcup, able to rotate, and the elastic support block that is attached tothe vehicle body. The relative angular movement between the spring cupand the elastic block is the result of a turning of the steered wheeland/or the compression of the suspension spring.

The suspension bump stop also transmits the axial loads between thespring and the vehicle body.

From document FR 2,779,096, a suspension bump stop device is known inwhich the rolling bearing includes an upper race placed inside a cap incontact with the elastic support block and a lower race in directcontact with the cup. The rolling bearing includes a cage fitted withsealing lips to seal the bearing.

However, the bearing seal thus obtained is not satisfactory.Specifically, the suspension bump stop rolling bearings are situatedunder the vehicle body and in the near vicinity of the wheels which,particularly during rainy weather, splash pollutants likely to enter thebearing.

Pollution of the bearing by external elements may, in the long run,adversely affect the operation of the bearing.

SUMMARY

Described herein is a suspension bump stop rolling bearing that is verytightly sealed while remaining axially and radially compact.

In one embodiment, a suspension bump stop rolling bearing capable oftransmitting both axial and radial loads while correctly distributingthe loads is described.

Finally, a suspension bump stop rolling bearing with a high degree ofimperviousness that may easily be assembled, cannot be dismantled and ischeap to fabricate is also described.

A vehicle suspension bump stop device is of the type including anangular contact rolling bearing forming a bump stop, a cup for a spring,and an elastic support block, the rolling bearing being placed betweenthe cup and the elastic support block secured to the vehicle chassis.The rolling bearing includes an upper race placed inside an upperannular cap forming an interface between said upper race and the elasticblock with which the upper cap is in contact, a lower race, and rollingelements placed between raceways of the upper and lower races. Thesuspension bump stop device includes an annular lower cap forming aninterface between the lower race and the cup with which the lower cap isin contact. The lower and upper caps each include a thick portion and athin portion, the thin portion of one cap being situated axiallyopposite the thick portion of the other cap, the lower and upper racesbearing against the thick portions of the lower and upper caps therebyforming an angular contact rolling bearing.

The placing of a thick portion opposite a thin portion makes it possibleto produce an angular contact rolling bearing of reduced axial andradial bulk. The particular shape of the caps including a thick portionand a thin portion provides a good distribution of the loads from a capto the cup or from a cap to the elastic support block while facilitatingthe formation on the caps of sealing means and/or the placing ofseparate seals, to protect the suspension bump stop rolling bearingeffectively.

Advantageously, one race has an external diameter substantially equal tothe internal diameter of the other race, so that the lower and upperraces may be obtained from one and the same blank to reduce theirfabrication cost. With such a race configuration, it is easy to obtainan angular contact rolling bearing with good operational qualities.

The ratio between the internal diameter of one outer race and theexternal diameter of the other race lies between 1 and 1.05. Dependingon the orientation of the rolling bearing angular contact, the upperrace is the race with the larger average diameter, or the lower race isthe race with the larger average diameter.

In an embodiment, the upper and lower caps define an internal space inwhich the upper and lower races are located, the upper and lower capsincluding sealing means to seal the internal space. The lower capcooperates with the upper cap to form an internal space in which therolling bearing of the suspension bump stop device lies and is thusprotected. The means of sealing the upper and lower caps interact toensure that the bearing is protected against the ingress of externalpollutants.

In one embodiment, a cap including a skirt extending axially toward theother cap and radially limiting the internal space, while forming anarrow sealing passage with the other cap. The presence of the skirtradially encloses, at the inner or outer periphery, the internal spacedefined between the upper and lower caps. The skirt forms a sealingmeans cooperating with the other cap to seal the internal space by meansof a narrow radial and/or axial passage.

One cap includes means of axial retention with the other cap. Thisproduces a compact assembly that cannot be dismantled and may be easilyhandled without the risk of being accidentally dismantled by anoperator.

In one embodiment, one cap includes a radially elastic lip extendingtoward a skirt of the other cap thereby forming a narrow passage andinteracting with a radial flange of the skirt to allow an axial motionin one direction while preventing an inverse axial motion. The lipinteracts with the skirt to produce a means of sealing the internalspace. The skirt interacts with the radial flange to produce a means ofaxial retention between the upper cap and the lower cap. The skirttherefore performs a dual function of axial retention and of sealing,capable of being produced at low cost and of allowing easy assembly ofthe suspension bump stop rolling bearing and ensuring that thesuspension bump stop rolling bearing cannot be accidentally dismantled.

To further improve the sealing of the rolling bearing, the suspensionbump stop device may include a seal placed on one cap, for example in anannular rib, and having a lip in contact with a radial portion of therace placed on the other cap, or with the other cap. If necessary, eachcap may include a seal interacting with the race placed on the other capor directly with the other cap. Hence, a seal provides improvedimperviousness, the means of sealing between the upper and lower capsproviding additional sealing.

Advantageously, a seal is injection overmolded onto one cap or dualinjection molded at the same time as the cap.

Another embodiment relates to a method of fabricating a rolling bearingincluding a lower race and an upper race, in which, in a thin annularcup, two annular races provided with toroidal portions are formed, theseportions having surfaces with, in cross section, a concave profile, saidsurfaces being suitable for forming raceways, one race having aninternal diameter substantially equal to the external diameter of theother race, the races being connected, the races are separated, and therecess radius of at least one race and/or the internal diameter of thelarger diameter race is reduced.

This fabrication method can easily be applied to a suspension bump stopdevice: the races are secured with lower and upper annular cups, rollingelements are placed between the races to form a suspension bump stopthrust bearing, the bearing is placed between a cup of a spring and anelastic support block secured to the vehicle chassis, the upper capforming an interface between said upper race and the elastic block withwhich it is placed in contact, the lower cap forming an interfacebetween the lower race and the cup with which it is placed in contact,each cap including a thick portion and a thin portion, the thin portionof one cap being situated axially opposite the thick portion of theother cap, the lower and upper races bearing against the thick portionsof the lower and upper caps thereby forming an angular contact rollingbearing. The races easily enable the fabrication of an angular contactrolling bearing that may take axial and radial loads.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention and its advantages will be better understood bystudying the detailed description of some embodiments taken asnonlimiting examples and illustrated by the appended drawings wherein:

FIG. 1 is a view in axial section of a suspension bump stop rollingbearing in the assembled state;

FIG. 2 is a view of the suspension bump stop rolling bearing accordingto FIG. 1;

FIG. 3 is a variant of a suspension bump stop rolling bearing accordingto FIG. 2; and

FIGS. 4 to 6 illustrate a method of fabricating two races used in thesuspension bump stop rolling bearings according to FIGS. 1 to 3.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and will herein be described in detail. Itshould be understood, however, that the drawing and detailed descriptionthereto are not intended to limit the invention to the particular formdisclosed, but on the contrary, the intention is to cover allmodifications, equivalents and alternatives falling within the spiritand scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION

In FIG. 1, a damper includes a cylinder, not shown, in which a pistoncan slide whose rod 1 is linked at its top end to an elastic supportblock 2 which bears against an element of the chassis 3 forming a seatwhile being secured to the latter. The elastic support block 2 includesan internal annular link element 4 made up of two portions 4 a and 4 bonto which the end of the damper piston rod 1 is mounted by means of anut 5, an annular external link element 6 used for securing to thechassis 3, an annular upper cup 7 acting as a seat for the bump stoprolling bearing 8, a rubber block 9 bonded to the surface of these threeparts and forming a link between the latter with filtration ofvibrations.

The external linking element 6 is attached to the chassis 3, for exampleby screwing or bolting. The upper cup 7 is placed axially on theinternal linking element 4, but is of greater diameter. Also shown isthe suspension spring 10 the top of which bears against a lower annularcup 11 which, in turn, bears against the bump stop rolling bearing 8.

The upper cup 7 includes a radial portion 7 a and a cylindrical axialportion 7 b extending from the larger diameter portion of the radialportion 7 a. The upper surface of the radial portion 7 a and theexternal surface of the cylindrical portion 7 b are in contact with therubber block 9 of the elastic support block 2.

The lower cup 11 includes a recess 11 a in which the end of the spring10 rests, a radial portion 11 b extending radially inward from therecess 11 a and a cylindrical portion 11 c extending axially toward theupper cup 7 a from the free inner edge of the radial portion 11 b.

The suspension bump stop 8, more clearly visible in FIG. 2, includes anupper race 12 and a lower race 13, between which are housed rollingelements 14, balls in this instance, retained circumferentially,regularly spaced by a cage 15 of synthetic material. The upper race 12and lower race 13 are formed of steel plate by cutting and pressing.

The upper race 12 includes a toroidal portion 12 a having in crosssection an internal concave quarter circle profile suitable for forminga toric raceway for balls, said toroidal portion 12 a being extendedoutward by a radial portion 12 b, extending from one lower edge of thetoroidal portion 12 a.

The lower race 13 includes a toroidal portion 13 a having in crosssection an internal concave quarter circle profile suitable for forminga toric raceway for balls, said toroidal portion 13 a being extendedinward by a radial portion 13 b, extending from one upper edge of thetoroidal portion 13 a. The internal diameter of the upper race 12 issubstantially equal to the external diameter of the lower race 13.

The suspension bump stop 8 includes an upper annular cap 16 and a lowerannular cap 17 of synthetic material such as a glass-fiber-filledpolyamide. The upper cap 16 includes a thick peripheral portion 18extended radially inward by a thin radial portion 19 of lesserthickness, from the top of the thick portion 18.

The thick portion 18 includes a radial surface 18 b oriented toward thelower cap 17 and a toroidal internal surface 18 a with, in crosssection, a concave profile oriented toward the lower cap 17 and radiallyinward, the internal surface 18 a connecting the thick portion 18 to thethin portion 19. The thick portion 18 is of a thickness that reducesradially inward. The upper cap 16 comprises an upper radial surface 16 aand an external cylindrical surface 16 b that are connected by a roundedbevel 16 c.

The upper cap 16 includes an internal skirt 20 extending axially towardthe lower cap 17 from the area of lesser diameter of the thin portion19. The cap 16 also includes an external skirt 21 extending axiallytoward the lower cap 17 from the area of greater diameter of the thickportion 18.

The thick portion 18 is of a shape that mates with the upper race 12,the convex external surface of the toroidal portion 12 a bearing againstthe toroidal internal surface 18 a of the thick portion 18, and thesubstantially radial portion 12 b projecting over the radial surface 18b of the thick portion 18.

The lower cap 17 includes a thick portion 22 of lesser diameter extendedradially outward and from a lower edge of the thick portion 22, via athin radial portion 23 of lesser thickness. The thick portion 22includes an external surface 22 a with, in cross section, a concaveprofile oriented outward, the external surface 22 a connecting the thickportion 22 to the thinner portion 23. The thick portion 22 is of athickness that reduces radially toward the outside. The lower cap 17includes a lower radial surface 17 a and a cylindrical internal surface17 b which are connected by a rounded bevel 17 c.

The thick portion 22 is of a shape that mates with the lower race 13,the concave profile internal surface of the toroidal portion 13 abearing against the external surface 22 a of the thick portion, theradial portion 13 b slightly overlapping the thick portion 22 of thelower cap 17.

The lower cap 17 includes an annular rib 24 extending axially toward theupper cap 16 from the thick portion 22. The diameter of the annular rib24 is greater than the diameter of the internal cylindrical surface 17b, while being less than the diameter of the lesser diameter area of theexternal surface 22 a. The lower cap 17 includes a radial surface 22 bsituated between the cylindrical surface 17 b and the annular rib 24,and a radial surface 22 c situated between the annular rib 24 and thetop edge of the external surface 22 a. The radial portion 13 b of thelower race 13 overlaps the radial surface 22 c coming radially close tothe annular rib 24.

The internal skirt 20 of the upper cap 16 extends axially close to theradial surface 22 b thereby forming a narrow radial passage. Theexternal skirt 20 surrounds the annular rib 24 thereby forming a narrowaxial passage. Thus, the skirt 20 interacts with the annular rib 24 toform a narrow passage means of sealing between the lower cap 17 and theupper cap 16.

The internal skirt 20 has an internal diameter substantially equal tothe internal diameter of the thick portion 22 of the lower cap 17.

The cap 17 includes a radially elastic lip 25, extending obliquelyoutward from the surface of an annular flange 25 a formed at the end ofgreater diameter of the portion of lesser thickness 23, and coming intocontact with or close to the internal surface of the external skirt 21of the upper cap 16. The lip 25 extends radially outward and axially onthe opposite side to the upper cap 16. The lip 25 makes it possible toproduce a narrow passage or, where appropriate, a friction contact meansof sealing between the upper cap 16 and lower cap 17.

The external skirt 21 includes at its opposite axial end to the uppercap 16 an annular flange 26 extending radially inward. The annularflange 26 allows axial motion in one direction of the lip 25 of thelower cap 17 that deforms radially inward and prevents the lip 25 frommoving axially in the opposite direction. Thus, the lower cap 17 may besecured axially to the upper cap 16. The flange 26 includes a truncatedcone shaped surface 26 a facing away from the upper cap 16 facilitatingthe deformation of the lip 25 when the lower cap 17 is inserted in theupper cap 16. The flange 26 includes a truncated cone shaped surface 26b facing toward the cap 16 against which surface the lip 25 bears if thelower cap 17 tends to move axially away from the upper cap 16,preventing the lower cap 17 and upper cap 16 from moving axially apart.

The lip 25 has a dual function of sealing and of axial retention. Thelip 25, in a single piece with the lower cap 17, may be easily obtainedat the same time as the lower cap 17. The lip 25 enables easy assemblyand axial retention with axial play where necessary.

The suspension bump stop 8 includes a seal 27 including a heel 28 placedand attached in an annular slot 29 of the lower cap 17 and a lip 30extending radially outward and axially toward the upper cap 16 andcoming into friction contact with the radial portion 12 b of the upperrace. The heel 28 of the seal 27 is situated axially facing the rollingelements 14 surrounding the free edge of the toroidal portion 13 a ofthe lower race 13.

The use of an upper cap 16 and a lower cap 17 allows the formation of aninterior space, delimited axially by the upper cap 16 and the lower cap17 and radially by the inner skirt 20 and outer skirt 21, in which spacethe races 12, 13 as well as the rolling elements 14 are placed. It iseasy to seal off the interior space.

The caps 16, 17 forming an interface respectively between the upper cup7 and the upper race 12, and between the lower race 13 and the lower cup11, transmit and distribute the axial and radial loads between the uppercup 7 and lower cup 11. Returning to FIG. 1, the upper cap 16 bearsaxially by its thick portion 18 and thin portion 19 against the annularportion 7 a of the upper cup 7 and is in contact by its thick portion 18with the cylindrical portion 7 b. The thick portion 18 transmits radialand axial loads to the upper cup 7. The thin portion 19 transmits mainlyaxial loads to the upper cup 7. Similarly, the lower cap 17 bearsaxially by its thick portion 22 and thin portion 23 against the annularportion 11 b of the lower cup and bears radially, by its thick portion22, against the axial portion 11 c.

Where appropriate, the upper cap 16 may be placed in direct contact withthe rubber block 9 without using the intermediate upper cup 7.

The lip 25 interacting with the annular flange 26 forms a means of axialretention between the upper cap 16 and the lower cap 17 so as to obtaina suspension bump stop rolling bearing 8 that is easy to assemble andcannot be dismantled, so that it can be handled by an operator withoutrisk of accidental dismantling.

To improve the sealing of the suspension bump stop rolling bearing 8,and as shown in FIG. 3, a second seal 31 may be installed, this sealhaving a heel 32 arranged radially in the lesser diameter area of thethin portion 19, attached in an annular slot 33 formed between theinterior skirt 20 and an annular flange 19 a of the portion of lesserthickness 19 of the upper cap 16, and having a lip 34 extendingobliquely, axially toward the lower cap 17 and radially outward andcoming into friction contact with the radial portion 13 b of the lowerrace 13. Thus, the seals 31, 27 provide an effective seal, improving thesealing already provided by the sealing means of the upper cap 16 andlower cap 17.

The presence of the thin portions 19, 23 extending radially and axiallyopposite the thick portions 22, 18 facilitates the attachment of theadditional seals 31, 27.

In the embodiment illustrated in FIG. 3, the radial surface 22 b isformed at a level axially offset downward relative to the radial surface22 c such that the exterior skirt 21 is more extended axially, theannular rib 24 being less extended axially to allow the passage of thelip 34, while retaining a narrow passage of dimensions similar to theembodiment illustrated before.

In the preceding embodiments, it is easy to obtain the upper cap 16 andlower cap 17 by molding. Advantageously, the seals 27, 31 may beovermolded directly onto the upper and lower caps 16, 17 or befabricated by dual injection molding at the same time as said caps 16,17.

The external diameter of the lower race 13 is substantially equal to theinternal diameter of the upper race 12. This particular configurationmeans that the upper race 12 and lower race 13 may be obtained from oneand the same blank, as illustrated in FIGS. 4 to 6.

In FIG. 4, an annular cup 35 made of thin sheet metal, formed forexample by cutting and pressing, includes two future races 36, 37connected together and separated symbolically in FIG. 4 by lines 38. Thesmaller diameter race 36 includes a toroidal portion 39, whose exteriorsurface 39 a has, in cross section, a concave profile substantially in aquarter circle, and a radial portion 40 extending inward from the areaof lesser diameter of the toroidal portion 39.

The race 37 extends from the opposite free edge of the race 36 to theradial portion 40. The race 37 includes a toroidal portion 41 whoseinner surface 41 a has, in cross section, a concave profilesubstantially in a quarter circle and includes a radial portion 42extending outward from the opposite free edge of the race 37 to the race36.

The concave profile surfaces 39 a, 41 a of the toroidal portions 39, 41of the races 36, 37 are suitable for forming raceways for rollingelements of a suspension bump stop rolling bearing, balls for example.

To obtain the lower and upper races, the races 36, 37 are separated, forexample by means of a blanking punch to cut out the material of the cup35 in a circle whose center passes through the axis of revolution of thecup 35 and which is delimited radially by the lines 38. A race 36 isobtained of external diameter substantially equal to the internaldiameter of the other race 37. The surface with concave profile 39 a hasa recess radius R1 indicated by a dotted circle 43.

FIG. 6 illustrates the race 37 after an additional forming operationduring which the radius of the recess of the race 37 is reduced toobtain a recess radius R2 less than R1, indicated by a dotted circle 44.In the same operation, the internal diameter of the race 37 may beslightly reduced so that the race 37 protrudes radially inward beyondthe pitch radius of the rolling bearing formed using the race 37 toensure that the free edge of the race 37 does not damage the rollingelements in the event of a high axial load. An identical operation maybe performed on the race 36.

Preferably, on the finished races, a recess radius R2 of the race 37should be identical to the recess radius of the race 36, the two recessradii being slightly greater than the radius of the balls of the rollingbearing. Preferably, the ratio between the final internal diameter ofthe race 36 and the final external diameter of the race 37 is between 1and 1.05.

Returning to FIGS. 1 to 3, and using the races 36 and 37 whose internaland external diameters have been modified to form the races 13 and 12,the free end of the toroidal portion 12 a of the upper race 12 and thefree end of the toroidal portion 13 a of the lower race 13 should notdamage the rolling elements 14 in the event of the transmission of amajor axial load by the suspension bump stop rolling bearing 8.

The process of fabricating the suspension bump stop rolling bearing 8allows the upper and lower races to be produced from one and the sameblank which reduces the cost of fabricating the suspension bump stoprolling bearing. In addition, using a simple additional operation, therecess radius of the lower race and/or of the upper race is reduced andthe correct behavior of the elements is ensured during the transmissionof major axial loads.

A suspension bump stop rolling bearing may be obtained including twocaps defining an interior space that is sealed by means of sealing ofthe caps interacting as well as by separate seals. The particularstructure of the caps produces a rolling bearing of reduced axial bulk,facilitating the installation of separate seals. The suspension bumpstop rolling bearing is able to transmit both axial and radial loads,the lower and upper caps providing a good distribution and a bettertransmission of the loads from the lower cup to the upper cup andvice-versa.

Further modifications and alternative embodiments of various aspects ofthe invention may be apparent to those skilled in the art in view ofthis description. Accordingly, this description is to be construed asillustrative only and is for the purpose of teaching those skilled inthe art the general manner of carrying out the invention. It is to beunderstood that the forms of the invention shown and described hereinare to be taken as the presently preferred embodiments. Elements andmaterials may be substituted for those illustrated and described herein,parts and processes may be reversed, and certain features of theinvention may be utilized independently, all as would be apparent to oneskilled in the art after having the benefit of this description to theinvention. Changes may be made in the elements described herein withoutdeparting from the spirit and scope of the invention as described in thefollowing claims. In addition, it is to be understood that featuresdescribed herein independently may, in certain embodiments, be combined.

1. A vehicle bump stop device of the type comprising an angular contactrolling bearing forming a bump stop, a cup for a spring, and an elasticsupport block, the rolling bearing being placed between the cup and theelastic support block secured to the vehicle chassis, the rollingbearing comprising an upper race placed inside an upper annular capforming an interface between said upper race and the elastic block withwhich the upper cap is in contact, a lower race and rolling elementsplaced between raceways of the upper and lower races, the vehicle bumpstop device further comprising an annular lower cap forming an interfacebetween the lower race and the cup with which the lower cap is incontact, each cap comprising a thick portion and a thin portion, thethin portion of one cap being situated axially opposite the thickportion of the other cap, the lower and upper races bearing on the thickportions of the lower and upper caps thereby forming an angular contactrolling bearing.
 2. The device as claimed in claim 1, wherein one racehas an external diameter substantially equal to the internal diameter ofthe other race, so that the lower race and upper race are obtained fromone and the same blank to reduce their fabrication cost.
 3. The deviceas claimed claim 1, wherein the ratio between the internal diameter ofone outer race and the external diameter of the other race lies between1 and 1.05.
 4. The device as claimed in claim 1, wherein the upper capand lower cap define an internal space in which the upper race and lowerrace are located, the upper and lower caps comprising sealing means toseal the internal space.
 5. The device as claimed in claim 1, whereinone cap comprises a skirt extending axially toward the other cap andradially limiting the internal space, while forming a narrow sealingpassage with the other cap.
 6. The device as claimed in claim 1, whereinone cap comprises axial means of retention with the other cap.
 7. Thedevice as claimed in claim 1, wherein one cap comprises a radiallyelastic lip extending toward a skirt of the other cap thereby forming anarrow passage and cooperating with a radial flange of the skirt toallow an axial motion in one direction while preventing an inverse axialmotion.
 8. The device as claimed in claim 1, further comprising a sealplaced on the cap and having one lip in contact with one radial portionof the race placed on the other cap, or with the other cap.
 9. Thedevice as claimed in claim 1, wherein a seal is injection overmoldedonto one cap or dual injection molded at the same time as the cap.
 10. Amethod of fabricating a rolling bearing comprising a lower race and anupper race, comprising: forming in a thin annular cup, two annular raceswith toroidal portions, these portions comprising surfaces with, incross section, a concave profile, said surfaces being suitable forforming raceways, one race having an internal diameter substantiallyequal to the external diameter of the other race, the races beingconnected; separating the races; and reducing the recess radius of atleast one race and/or the internal diameter of the larger diameter race.11. The fabrication method as claimed in claim 10, further comprisingsecuring the races with lower and upper annular cups, rolling elementsare placed between the races to form a suspension bump stop thrustbearing, the bearing is placed between a cup of a spring and an elasticsupport block secured to the vehicle chassis, the upper cap forming aninterface between said upper race and the elastic block with which it isplaced in contact, the lower cap forming an interface between the lowerrace and the cup with which it is placed in contact, each cap comprisinga thick portion and a thin portion, the thin portion of one cap beingsituated axially opposite the thick portion of the other cap, the lowerand upper races bearing against the thick portions of the lower andupper caps thereby forming an angular contact rolling bearing.
 12. Anangular contact rolling bearing for a vehicle suspension bump stopdevice, the rolling bearing comprising an upper race arranged in anannular upper cap, the cap being designed to come into contact with abearing element thereby forming an interface between said upper race andthe bearing element, a lower race and rolling elements placed betweenraceways of the upper and lower races, wherein the angular contactrolling bearing further comprises an annular lower cap designed to comeinto contact with another bearing element thereby forming an interfacebetween the lower race and the other bearing element, each capcomprising a thick portion and a thin portion, the thin portion of onecap being situated axially opposite the thick portion of the other cap,the lower and upper races coming to bear against the thick portions ofthe lower and upper caps thereby forming an angular contact rollingbearing.
 13. The rolling bearing as claimed in claim 12, wherein onerace has an external diameter substantially equal to the internaldiameter of the other race, so that the lower race and upper race areobtained from one and the same blank to reduce their fabrication cost.14. The rolling bearing as claimed in claim 12, wherein the ratiobetween the internal diameter of one outer race and the externaldiameter of the other race lies between 1 and 1.05.
 15. The rollingbearing as claimed in claim 12, wherein the upper cap and lower capdefine an internal space in which the upper race and lower race arelocated, the upper and lower caps comprising sealing means to seal theinternal space.
 16. The rolling bearing as claimed in claim 12, whereinone cap comprises a skirt extending axially toward the other cap andradially limiting the internal space, while forming a narrow sealingpassage with the other cap.
 17. The rolling bearing as claimed in claim12, wherein one cap comprises axial means of retention with the othercap.
 18. The rolling bearing as claimed in claim 12, wherein one capcomprises a radially elastic lip extending toward a skirt of the othercap thereby forming a narrow passage and cooperating with a radialflange of the skirt to allow an axial motion in one direction whilepreventing an inverse axial motion.
 19. The rolling bearing as claimedin claim 12, further comprising a seal placed on one cap and having onelip in contact with one radial portion of the race placed on the othercap, or with the other cap.
 20. The rolling bearing as claimed in claim12, wherein a seal is injection overmolded onto one cap or dualinjection molded at the same time as the cap.